1. Field of the Invention
The present invention relates to a liquid gas generating composition and to a gel-like gas generating composition that can be employed in an airbag apparatus or the like for an automobile.
2. Description of Related Arts
The conventional gas generating compositions sometimes contain a substance causing to generate a hazardous substance such as halogens in released gases. However, because hydroxyammonium nitrate (HAN) does not contain source substances generating toxic substances, the released gases can be cleaned by using HAN as an oxidizing agent.
Further, in the conventional gas generating compositions, a proportionate amount of combustion residues derived from the oxidizing agent is ejected together with the high-temperature gas. Therefore, a large amount of filtering material has to be incorporated in the airbag inflator structure. However, where HAN is used as the oxidizing agent, the residues are not formed or practically not formed, thereby making the filtering material unnecessary or requiring only a small amount thereof to be incorporated in the structure.
JP-A No. 11-1386 discloses a solid propellant obtained by mixing HAN and a binder serving as a fuel component, such as a polysulfide, polyvinyl chloride, polyurethane, a polyesters, a carboxyl-terminated polybutadiene, a hydroxyl-terminated polybutadiene, and a glycidylazide polymer.
U.S. Pat. No. 6,228,193 discloses a gas generating agent including HAN and a gelling agent. Polyvinyl alcohol is presented as an example of the gelling agent, and the content ratio of the gelling agent is described to be 5 to 25 mass %.